Device for compacting a substrate

ABSTRACT

A device for compacting a substrate, comprising an under carriage with a base arranged on the under carriage; a superstructure which is connected to the under carriage so as to transmit a force; a vibration exciter, by means of which at least the base of the undercarriage can be caused to vibrate and a contact plate, which is arranged on the base, said contact plate being arranged on a base lower face facing away from the superstructure such that the contact plate directly contacts the substrate to be compacted during the operation of the device. The contact plate and the base are connected together in a non-destructively releasable manner so as to transmit a force.

RELATED APPLICATIONS

This application is a continuation of International patent applicationPCT/EP2017/052093 filed on Feb. 1, 2017, claiming priority from Germanpatent application DE 10 2016 103 024.4 filed on Feb. 22, 2016, both ofwhich are incorporated in their entirety by this reference.

FIELD OF THE INVENTION

The invention relates to a device for compacting a substrate, the devicecomprising:

an under carriage with a base plate arranged on the under carriage;

a superstructure that is connected with the under carriage so that aforce is transferrable from the superstructure to the undercarriagewherein the superstructure includes a vibrator that is capable for forceat least the base plate of the under carriage to vibrate; and

a contact plate arranged at the base plate on a bottom side of the baseplate that is oriented away from the superstructure so that the contactplate comes in direct contact with the substrate to be compacted duringoperation of the device,

wherein the contact plate and the base plate are connected with eachother so that a force is transferable between the contact plate and thebase plate and the contact plate and the base plate are disengageablefrom each other without damage to the contact plate or the base plate.

The application also relates to a method for mounting a contact plate ata base plate of a device for compacting a substrate, the methodcomprising the steps:

a) positioning the base plate and the contact plate relative to oneanother so that the base plate contacts the contact plate at least witha substantial entirety of its surface area,

b) connecting the base plate and the contact plate so that a force istransferrable between the base plate and the contact plate and amovement of the contact plate relative to the base plate is blocked atleast in a forward direction of the device.

The device described supra can be for example a so called vibratingplate which is moved over the substrate to be compacted by remotecontrol or manually. If the device is moved by hand it typicallyincludes a tow bar by which a person operating the device can steer thedevice.

The “base plate” of the device designates the component through whichthe device typically contacts the ground to be compacted. Therefore, thebase plate is the component by which the device transfers the generatedforces to the substrate to be compacted. Typically, the base plate isformed by a steel element with several millimeters thickness.

The device according to the invention includes an additional contactplate on a side of the base plate that is oriented towards the substratewherein the contact plate contacts the ground to be compressed duringoperations of the device in lieu of the base plate. A contact plate ofthis type can be formed for example by a plastic material, wherein thecontact plate can be used in particular to dampen forces impacting thesubstrate in order to prevent the substrate from being damaged. It isalso conceivable that the contact plate is formed from steel and assumesthe function of a wear protection plate which protects the base plate ofthe device against direct impact of forces.

The term “plate” according to the instant application with respect tothe base plate and the contact plate means that the components typicallyhave a thickness which significantly undercuts the other dimensions ofthe respective components. In particular a thickness of the base plateas well as of the contact plate is typically not more than 30 mm whereasa length and a width of the respective plate is typically severalhundred millimeters.

A connection between the contact plate and the base plate that isdisengageable without damage is a connection that can be engaged anddisengaged again at will without one of the plates getting damaged, Inparticular it is conceivable that the contact plate is connected by afastener, e.g., a threaded bolt at the base plate. It is appreciatedthat this connection can be disengaged again at will so that neither thebase plate nor the contact plate is damaged.

The “force transmitting connection” between the base plate and thecontact plate does not have to be provided directionally independent. Inorder to be able to operate the device including the contact plate in asensible manner it is typically only required that a relative movementbetween the plates in a forward direction of the device is prevented bythe force transmitting connection between the base plate and the contactplate. This means that the contact plate should not disengage from thebase plate during a forward movement of the device which represents itsprimary operating direction so that the device including its base platemoves forward while the contact plate remains stationary.

As a matter of principle, it is conceivable that the force transmittingconnection between the base plate and the contact plate acts in otherdirections relative to the device. A directionally independent couplingof base plate and contact plate, however, is not implied by thecurrently used term “force transmitting connection”.

BACKGROUND OF THE INVENTION

Devices and methods of the type recited supra are known in the art. Asdescribed supra the contact plates can be wear protection plates as wellas insulation plates.

Embodiments of the generic device are disclosed in the documents EP 0914 523 B1 and DE 201 05 765. Furthermore, reference is made to theGerman patent DE 10 2012 200 908 B1 owned by applicant.

The devices disclosed in the documents recited supra have in common thatthe provided contact plates are arranged at the base plates requiringtools for assembly and disassembly. Thus, as illustrated supra arespective contact plate is attached at the base plate itself and on theother hand side the contact plate is attached by a connectionarrangement at the superstructure of the device. In any case it isnecessary for mounting or dismounting a prior art contact plate to usetools and fasteners. This is disadvantageous in that proper tools or therequired fasteners are typically not on hand at the construction sitewhen the contact plate has to be mounted or dismounted and consequentlythe work flow initially has to be interrupted in order to get thenecessary parts.

BRIEF SUMMARY OF THE INVENTION

The invention relates to a device for compacting a substrate, the devicecomprising:

-   -   an under carriage with a base plate arranged on the under        carriage;    -   a superstructure that is connected with the under carriage so        that a force is transferrable from the superstructure to the        undercarriage wherein the superstructure includes a vibrator        that is capable for force at least the base plate of the under        carriage to vibrate; and    -   a contact plate arranged at the base plate on a bottom side of        the base plate that is oriented away from the superstructure so        that the contact plate comes in direct contact with the        substrate to be compacted during operation of the device,

wherein the contact plate and the base plate are connected with eachother so that a force is transferable between the contact plate and thebase plate and the contact plate and the base plate are disengageablefrom each other without damage to the contact plate or the base plate.

The application also relates to a method for mounting a contact plate ata base plate of a device for compacting a substrate, the methodcomprising the steps:

a) positioning the base plate and the contact plate relative to oneanother so that the base plate contacts the contact plate at least witha substantial entirety of its surface area,

b) connecting the base plate and the contact plate so that a force istransferrable between the base plate and the contact plate and amovement of the contact plate relative to the base plate is blocked atleast in a forward direction of the device.

The device described supra can be for example a so called vibratingplate which is moved over the substrate to be compacted by remotecontrol or manually. If the device is moved by hand it typicallyincludes a tow bar by which a person operating the device can steer thedevice.

The “base plate” of the device designates the component through whichthe device typically contacts the ground to be compacted. Therefore, thebase plate is the component by which the device transfers the generatedforces to the substrate to be compacted. Typically, the base plate isformed by a steel element with several millimeters thickness.

The device according to the invention includes an additional contactplate on a side of the base plate that is oriented towards the substratewherein the contact plate contacts the ground to be compressed duringoperations of the device in lieu of the base plate. A contact plate ofthis type can be formed for example by a plastic material, wherein thecontact plate can be used in particular to dampen forces impacting thesubstrate in order to prevent the substrate from being damaged. It isalso conceivable that the contact plate is formed from steel and assumesthe function of a wear protection plate which protects the base plate ofthe device against direct impact of forces.

The term “plate” according to the instant application with respect tothe base plate and the contact plate means that the components typicallyhave a thickness which significantly undercuts the other dimensions ofthe respective components, In particular a thickness of the base plateas well as of the contact plate is typically not more than 30 mm whereasa length and a width of the respective plate is typically severalhundred millimeters.

A connection between the contact plate and the base plate that isdisengageable without damage is a connection that can be engaged anddisengaged again at will without one of the plates getting damaged. Inparticular it is conceivable that the contact plate is connected by afastener, e.g., a threaded bolt at the base plate. It is appreciatedthat this connection can be disengaged again at will so that neither thebase plate nor the contact plate is damaged.

The “force transmitting connection” between the base plate and thecontact plate does not have to be provided directionally independent. Inorder to be able to operate the device including the contact plate in asensible manner it is typically only required that a relative movementbetween the plates in a forward direction of the device is prevented bythe force transmitting connection between the base plate and the contactplate. This means that the contact plate should not disengage from thebase plate during a forward movement of the device which represents itsprimary operating direction so that the device including its base platemoves forward while the contact plate remains stationary.

As a matter of principle, it is conceivable that the force transmittingconnection between the base plate and the contact plate acts in otherdirections relative to the device. A directionally independent couplingof base plate and contact plate, however, is not implied by thecurrently used term “force transmitting connection”.

The invention relates to a device for compacting a substrate, the devicecomprising:

-   -   an under carriage with a base plate arranged on the under        carriage;    -   a superstructure that is connected with the under carriage so        that a force is transferrable from the superstructure to the        undercarriage wherein the superstructure includes a vibrator        that is capable for force at least the base plate of the under        carriage to vibrate; and    -   a contact plate arranged at the base plate on a bottom side of        the base plate that is oriented away from the superstructure so        that the contact plate comes in direct contact with the        substrate to be compacted during operation of the device,

wherein the contact plate and the base plate are connected with eachother so that a force is transferable between the contact plate and thebase plate and the contact plate and the base plate are disengageablefrom each other without damage to the contact plate or the base plate.

The application also relates to a method for mounting a contact plate ata base plate of a device for compacting a substrate, the methodcomprising the steps:

a) positioning the base plate and the contact plate relative to oneanother so that the base plate contacts the contact plate at least witha substantial entirety of its surface area,

b) connecting the base plate and the contact plate so that a force istransferrable between the base plate and the contact plate and amovement of the contact plate relative to the base plate is blocked atleast in a forward direction of the device.

The device described supra can be for example a so called vibratingplate which is moved over the substrate to be compacted by remotecontrol or manually. If the device is moved by hand it typicallyincludes a tow bar by which a person operating the device can steer thedevice.

The “base plate” of the device designates the component through whichthe device typically contacts the ground to be compacted. Therefore, thebase plate is the component by which the device transfers the generatedforces to the substrate to be compacted. Typically, the base plate isformed by a steel element with several millimeters thickness.

The device according to the invention includes an additional contactplate on a side of the base plate that is oriented towards the substratewherein the contact plate contacts the ground to be compressed duringoperations of the device in lieu of the base plate. A contact plate ofthis type can be formed for example by a plastic material, wherein thecontact plate can be used in particular to dampen forces impacting thesubstrate in order to prevent the substrate from being damaged. It isalso conceivable that the contact plate is formed from steel and assumesthe function of a wear protection plate which protects the base plate ofthe device against direct impact of forces.

The term “plate” according to the instant application with respect tothe base plate and the contact plate means that the components typicallyhave a thickness which significantly undercuts the other dimensions ofthe respective components. In particular a thickness of the base plateas well as of the contact plate is typically not more than 30 mm whereasa length and a width of the respective plate is typically severalhundred millimeters.

A connection between the contact plate and the base plate that isdisengageable without damage is a connection that can be engaged anddisengaged again at will without one of the plates getting damaged. Inparticular it is conceivable that the contact plate is connected by afastener, e.g., a threaded bolt at the base plate. It is appreciatedthat this connection can be disengaged again at will so that neither thebase plate nor the contact plate is damaged.

The “force transmitting connection” between the base plate and thecontact plate does not have to be provided directionally independent. Inorder to be able to operate the device including the contact plate in asensible manner it is typically only required that a relative movementbetween the plates in a forward direction of the device is prevented bythe force transmitting connection between the base plate and the contactplate. This means that the contact plate should not disengage from thebase plate during a forward movement of the device which represents itsprimary operating direction so that the device including its base platemoves forward while the contact plate remains stationary.

As a matter of principle, it is conceivable that the force transmittingconnection between the base plate and the contact plate acts in otherdirections relative to the device. A directionally independent couplingof base plate and contact plate, however, is not implied by thecurrently used term “force transmitting connection”.

Thus, it is an object of the invention to simplify mounting anddismounting a contact plate at a device for compressing a substratecompared to the prior art.

The object is achieved by the device according to the invention recitesupra in that the contact plate includes at least one connection portionthat is configured to directly engage the base plate through formlocking, wherein the connection portion is formed at the remainingcontact plate so that the connection portion extends in an installedcondition of the contact plate starting from a bottom side of thecontact plate to a top side of the contact plate oriented towards thesuperstructure and engages the top side at this location. Putdifferently the connection portion is advantageously configured so thatit envelops the base plate in a form locking manner at least in acorresponding portion. This engagement between the contact plate and thebase plate is thus provided so that a form locking connection betweenthe contact plate and the base plate is established or establishablesolely due to the form locking connection between the contact plate andthe base plate.

A “directly form locking connection” according to the instantapplication is a connection that provides form locking wherein thepartners of the form locking connection are the contact plate and thebase plate. The specification of this form locking connection as“direct” means that no separate fasteners are used to provide the formlocking connection, like e.g. bolt shaped fasteners which penetrate thebase plate as well as the contact plate and thus provide a form lockingengagement of both components with each other. A form locking connectionof the latter type designates only “an indirect” form locking connectionaccording to the instant application. Indirectly form lockingconnections of this type are well known in the art and are not suitableto implement the advantages of subject matter of the invention which aredescribed infra.

Establishing a force transmitting connection “solely through the effectof the connection portion” means according to the invention that theform locking connection between the contact plate and the base plate isconfigured to facilitate a force transmission between the recitedcomponents. This force transmission is provided so that the device isconfigured to compress a substrate solely through the effect of thedirectly from locking connection of contact plate and base plate. Thus,it is not necessary to couple the contact plate and the base plate witheach other by separate connection devices or similar in addition to thedirect form locking. The instant invention however does not exclude thatthe contact plate and the base plate are connected with each other byadditional fasteners to provide form locking or friction locking howeverthis additional connection is not required to operate the device.

In particular it is conceivable that the contact plate includes pluralconnection portions which engage the base plate in a form locking mannerat several locations, this means in different form locking portions. Inparticular the contact plate can include a respective connection portionof the type described supra at its two front corners. Through carefulplacement of several connection portions thus a form locking connectioncan be provided between the contact plate and the base plate in severaldirections so that a movement of the contact plate relative to the baseplate is blocked independently from a movement direction of the entiredevice. In particular it is conceivable that at least one connectionportion of the contact plate reaches around the base plate in a cornerportion so that at least a portion of the connection portion of thecontact plate frames the forward oriented outer edge of the base plateand at least one additional portion of the connection portion frames alateral edge of the base plate. Advantageously the contact plateincludes a respective connection portion in both forward corner portionsviewed in the forward direction of the device. A correspondingengineering design can be derived from the embodiment described infra.

The force transmission based on the direct form locking is thusconfigured at least so that the device can perform a forward motionduring operations without the contact plate and the base platedisengaging from each other. Put differently the form locking connectionbetween the contact plate and the base plate blocks a relative movementof both components at least parallel to the forward direction of thedevice. Additionally, it is certainly possible that the direct formlocking between the components also facilitates a sideways movement or abackward movement of the device without the contact plate and the baseplate performing a movement relative to each other. This will beseparately described infra. A form locking thus configured between thecomponents is not mandatory for the primary success of the inventionsince the device typically moves forward during operations.

The device according to the invention has many advantages. In particularit is possible through the device to couple the contact plate and thebase plate with each other without requiring additional connectors. Forexample, it is not necessary to bolt the contact plate and the baseplate together. This has the essential advantage that no additionalelements are required at the construction site to mount the contactplate in order to start operating the device with the contact plate.Accordingly, it is not necessary to look for associated tools or to buyfasteners. Furthermore, fasteners cannot be lost, contaminated ordamaged or become unusable in other ways so that replacement would berequired. This significantly improves work flow at a construction sitecompared to the prior art. The same applies for the moment in time whenthe contact plate shall be disengaged from the base plate. Thus, thedevice according to the invention only requires to disengage thepreviously established form locking and to remove the contact plate.Labor intensive disengagement of plural bolted connections or similar istherefore not required.

Thus, it is particularly advantageous in this context to run the devicewhich can be advantageously provided as a vibrating plate onto thecontact plate in operating condition, in particular from a rear end ofthe contact plate in a direction towards a front end. In order toconnect the contact plate with the base plate of the device it is onlyrequired for this procedure to place the contact plate onto thesubstrate and to run the run the device on the contact plate which canbe performed solely by the drive arrangement of the device andoptionally supported by muscle force of the operator of the device. Whenthe base plate is run onto the contact plate the base plate and thecontact plate eventually engage so that a force is transferable betweenthem. After reaching this condition the device can be used directlytogether with the contact plate without having to take additionalmeasures.

In this context it can be particularly advantageous when at least oneedge side of the contact plate, in particular a rear edge side isconfigured flat so that the device with the base plate can run onto thecontact plate at this edge side, Advantageously a thickness of thecontact plate at the edge side should not be more than 7 centimetersadvantageously not more than 5 centimeters, further advantageously notmore than 4 centimeters.

In a particularly advantageous embodiment of the device according to theinvention the connection between the contact plate and the base plate iscompletely free from any additional fasteners. At least for theperforming a forward movement of the device this applies as a matter ofprinciple according to the invention. However, it can also be possibleto couple the base plate and the contact plate with each other withadditional connectors in addition to the directly form lockingconnection in order to facilitate e.g. a sideways movement or backwardmovement of the device. In the illustrated advantageous embodiment ofthe device an additional fastener is not required either for these typesof movements of the device. Put differently the direct form lockingbetween the base plate and the contact plate is advantageouslyconfigured so that the device is usable in several movement directionscompletely independently from additional fasteners.

Furthermore, a device is particularly advantageous where the contactplate and the base plate are connectable with each other without toolsand disengageable from each other without tools. With this embodiment itis possible at the construction site anytime to connect the contactplate and the base plate with one another or to disengage them from eachother. There is no need to buy any tools. This simplifies operations ofthe device according to the invention even further.

In a particularly advantageous embodiment of the device according to theinvention the contact plate is provided in one piece. This applies inparticular for embodiments where the contact plate is formed by asynthetic material. In particular in cases where a contact plate is usedfor protecting the ground to be compressed against damages and/or forreducing construction noise (insulation plate) contact plates are beingused that are comparatively soft so that they have a damping effect.Thus, contact plates are being used in particular which are made fromVulkollan®. This is a polyester urethane rubber material which has arubbery consistency and a permanent resistance against mechanical loads.Other comparable synthetic materials can certainly also be advantageous.The embodiment of a one-piece contact plate is particularly simple whenit is made from a synthetic material since a material of this type canbe easily formed into any shape and can thus be adapted for example tovarious base plate geometries.

The device according to the invention is furthermore advantageous whenthe contact plate has at least one outer collar that extendsperpendicular to its base surface and which forms a lateral contactsurface for a corresponding outer edge of the base plate in an installedcondition of the contact plate. This collar of the contact plate isadvantageously provided at least at longitudinal sides of the contactplate, further advantageously circumferentially so that so to speak thecomplete circumferential outer edge of the base plate is framed by theouter collar of the contact plate. Thus, the collar of the contact plateis configured so that it blocks a movement of the base plate relative tothe contact plate in a direction of the collar of the contact plate.

In another advantageous embodiments of the device according to theinvention the contact plate is made from a material with a stiffnessthat is far below a stiffness of the base plate. Far below according tothe instant application means that the stiffness of the contact platehas at the most 25% of the stiffness of the base plate, advantageouslyat the most 5% of the stiffness of the base plate further advantageouslyat the most 0.5% of the stiffness of the base plate. In the typical casewhere the base plate is made from steel and the contact plate is madefrom a polyester urethane rubber material e.g. Vulkollan® this yields aratio of the stiffnesses of 200,000 N/mm² to 100 N/mm². The stiffness ofthe contact plate in this case is only 0.05% of the stiffness of thebase plate.

The device according to the invention can be particularly advantageouswhen it includes at least one locking element through which the contactplate is lockable at the base plate. This locking element can beconfigured at the undercarriage of the device, in particular at the baseplate or at the contact plate. Advantageously the locking element isconfigured at the contact plate. When this is the case it is furthermoreadvantageous when the locking element is configured integral in onepiece with the contact plate.

The locking element can be for example a type of clip which is deflectedby applying a force for example by stepping onto a transmission surfacewith a foot, wherein the locking element is deformed elastically. Inthis elastically deformed condition the locking element can be arrangedat the base plate so that it establishes form locking with the baseplate after the force is removed and the elastic deformation springsback wherein the locking element envelops the base plate in a forminglocking manner. In order to apply the described force, it isparticularly advantageous when the locking element extends in an edgeportion of the contact plate, in particular when it extends from theedge portion in a direction that is oriented away from the device. Thisway it is possible in a particularly simple manner to load the lockingelement with a torque and deflected in this manner.

Arranging a locking element at the device, in particular at the contactplate is particularly advantageous in cases where a relative movementbetween the contact plate and the base plate is blocked in alldirections of the device by direct form locking. Using the interlockingelement, it is then possible to disengage a form locking of this type atleast in a movement direction of the device and to move the device inthis direction so that a relative movement between the contact plate andthe remaining device is provided. Put differently the remaining devicecan be run off the contact plate in a particularly simple manner.

In proving upon the method described supra the object is achievedaccording to the invention by performing the following method step:

c) moving the base plate relative to the contact plate so that the baseplate moves into at least one connection portion of the contact plate sothat the base plate and the contact plate are directly connected witheach other through form locking after the base plate is inserted intothe connection portion.

Insertion according to the instant application is a translatoricrelative movement between the contact plate and the base plate. Inparticular the insertion is performed so that the contact plate isplaced onto a substrate and then the base plate or the remaining devicein its entirety is moved onto the contact plate using normal drivingoperations of the device until the base plate is eventually insertedinto the connection portion of the contact plate so that indirect formlocking is provided. Advantageously the device can be moved from a rearend of the contact plate in a direction towards its front end, whereinthe base plate moves into a connection portion of the contact plateduring this movement.

The method according to the invention has many advantages. In particularit facilitates connecting the contact plate with the base plate withoutusing tools. The advantages of this method have already been describedsupra. It is appreciated that the method according to the invention canbe performed in a particularly simple manner by the device according tothe invention that is described supra.

Independently from the method step c) described supra a method can beparticularly advantageous which includes the following method steps:

d) after positioning the base plate on the contact plate elasticallyexpanding the contact plate at least in one connection portion by amounting force,

e) moving at least a portion of the expanded connection portion over anedge of the base plate and subsequently removing the mounting force sothat the contact plate springs back into its starting position where itwas arranged without being loaded by the mounting force, wherein atleast a portion of the connecting portion of the contact plate attachesto a top side of the base plate and engages the base plate directlythrough form locking.

The method step d) and e) recited supra can also be combined with themethod step c) described supra

For performing the method steps d) and e) it is required that thecontact plate is made from a material which is elastically deformable bya force that can be applied by a human without any auxiliary devices.Thus, in particular a synthetic material is suitable in particular apolyester urethane rubber material.

Also, the second method recited herein has the advantages recited suprain conjunction with the first method. In particular the method can beperformed without tools or other auxiliary devices at a constructionsite. The force transmitting connection between the base plate and thecontact plate is thus always achieved by direct form locking betweenboth components.

BRIEF DESCRIPTION OF THE DRAWINGS

The device and the method according to the invention are subsequentlydescribed in more detail based on an embodiment with reference todrawing figures, wherein:

FIG. 1 illustrates a device according to the invention in a perspectiveview;

FIG. 2 illustrates a perspective view of an undercarriage of the deviceaccording to the invention wherein the undercarriage includes a baseplate with a contact plate arranged thereon; and

FIG. 3 illustrates a perspective view of a contact plate according tothe invention.

DETAILED DESCRIPTION OF THE INVENTION

The embodiment that is illustrates in FIGS. 1-3 includes a device 1 forcompacting a substrate. The device 1 is formed by a hand operatedvibrating plate. The device 1 includes a superstructure 4 and an undercarriage 2, wherein the superstructure 4 and the under carriage 2 areconnected with each other in a force transmitting manner. A vibrationexciter is arranged at the super structure 4 and configured to force thesuper structure 4 and the undercarriage 2 to vibrate due to the forcetransmitting connection. A substrate that respectively has to becompacted is compactable by the vibration that is excited by thevibration exciter. The super structure 4 cooperates with a tow bar 5which is arranged at the superstructure 4 with buffer elements arrangedthere between. The device 1 is controllable overall by the tow bar 5 bya person operating the device 1. In particular a movement direction ofthe device 1 can be influenced by the tow bar 5.

A base plate 3 is arranged at the undercarriage 2 and configured to comeinto direct contact with the respective substrate to be compacted. Thebase plate 3 is typically formed by a particularly wear-resistantmaterial, in particular steel, is appreciated that the base plate 3 isexposed to significant operating forces during operation of the device 1according to the invention which leads to a strong wear of the baseplate 3. Due to its particularly high stiffness, the substrate to becompacted is subjected to significant forces, In typical applicationswhere the device 1 is used for compacting lose ground, e.g., sandyground, an impact of the force on the ground, in particular a frictionforce imparted by the baseplate, is irrelevant. However, in situationswhere a substrate is processed whose surface properties are to complywith optical requirements directly using the base plate 3 on thesubstrate can lead to undesirable damages to the surface. In order toprevent damages, the substrate 3 is provided with a contact plate 6 inthe illustrated embodiment which acts as a damper plate. The contactplate 6 is formed from a polyester urethane rubber. Due to reducedstiffness of the material of the contact plate 6 compared to thematerial of the base plate 3, the contact plate is configured to evenlydistribute forces that are applied from the base plate 3 to thesubstrate to be compacted and thus to avoid a punctiform loading of thesubstrate and in particular of its surface.

The base plate 3 and the contact plate 6 are connected with each otherin a force transmitting manner. Thus, the contact plate 6 includes twoforward connection portions 8 that are arranged in a forward end section11 of the contact plate 6. The connections portions 8 are configured toengage corresponding form locking portions 10 of the base plate 3through form locking. In the illustrated embodiment this is facilitatedin that the connection portions 8 reach around the base plate 3 inforward corner portions of the base plate 3. Thus, the material of thecontact plate 6 is run in the connection portions 8 over a front edge 12of the base plate 3 to a top side 9 of the baseplate 3. There thematerial extends above the topside 9 of the base plate 3 and thusenvelopes the base plate 3 in its form locking portions 10 through formlocking. Put differently, the contact plate 6 is provided as a negativeof the base plate 3 in connection portions of the contact plate 6, sothat the base plate 3 engages the connection portions 8 of the contactplate 6 with form locking portions 10 of the base plate 3 preciselyfitting.

This creates a form locking connection between the contact plate 6 andthe base plate 3 which provides form locking according to the instantapplication. This form locking between the connection portion 8 of thecontact plate 6 and the form locking portions 10 of the base plate 3provides that the base plate 3 is not movable in a forward direction 17of the device 1 relative to the contact plate 6. Put differently, thecontact plate 6 is dragged along due to the forward movement of the baseplate 3 during the forward movement of the device 1.

It is appreciated that no tools are required to form the form lockingconnection between the contact plate 6 and the base plate 3 describedsupra. Advantageously the contact plate 6 is placed on a substrate formmounting and then the remaining device 1 is run onto the contact plate 6through a forward movement until the base plate 3 completely engagesconnection portions 8 of the contact plate 6 with forward form lockingportions 10. As soon as this is the case, mounting the contact plate 6at the base plate 3 is substantially completed.

As evident in particular in FIGS. 2 and 3 of the instant application thecontact plate 6 is provided with a circumferential collar 15 adjacent tothe connection portions 8 wherein the circumferential collar 15 extendsperpendicular to a base plate 14 of the contact plate 6. The collar 15is configured along an outer portion of the contact plate 6 so that itis configured to engage with a corresponding outer edge 16 of the baseplate 3 through form locking. This cooperation of the contact plate 6with the base plate 3 is evident in particular from the illustrationaccording to FIG. 2.

The circumferential collar 15 of the contact plate 6 provides that inaddition to blocking a relative movement between the base plate 3 andthe contact plate 6 in the forward direction 17 of the device 1 relativemovements in the backward direction 18 and in the sideward direction areblocked. This way it is possible to move the device 1 according to theinvention in any direction without causing an unintentionaldisengagement of the contact plate 6 from the base plate 3.

In a rear end portion of the contact plate 6 the contact plate 6includes a total of two locking elements 13. The locking elements 13 areconfigured to provide reversible form locking between the contact plate6 and the base plate 3. For this purpose the locking elements 13 arerespectively provided with a form locking section 19 extending towards acenter of the contact plate 6 wherein the form locking section isconfigured to engage a top side 9 of the base plate 3 in a form lockingmanner. Differently from the forward connection portions 8 of thecontact plate 6 the form locking sections 19 are provided significantlysmaller so that it is possible to move a respective form locking section19 by displacing the respective entire locking element 13 so that itdoes not engage the base plate 3 through a form locking engagementanymore. Thus, the interlocking elements 13 include a transmissionsection 20 that extends away from the contact plate 6 and which can bedisplaced in a particularly simple manner by stepping on it with a foot.

During dismounting of the contact plate 6 the directly form lockingconnection between the contact plate 6 and the base plate 3 can bedisengaged in a particularly simple manner wherein the remaining device1 can be moved in the backward direction 18 relative to the contactplate 6 after disengageing the locking elements from the base plate 3until the contact plate 6 and the remaining device 1 are providedseparate from each other again. Thus, it is appreciated that thematerial of the contact plate 6 is elastic enough so that it can deformunder the mass of the remaining device 1 so that the device 1 can moveover the contact plate 6 in spite of an upward curved configuration ofthe contact plate 6 in its rear end portion 21 without damaging thecontact plate 6.

Alternatively or in addition to the form locking portions 8 illustratedherein, it is conceivable that the contact plate 6 has one or pluralconnection portions at least in sections along its outer edge,advantageously circumferentially wherein the connection portions areconfigured so that they can be expanded by elastic deformation and canbe placed in this manner over the base plate 3 in a manner that issimilar to the locking elements 13 described supra. As a result, it isonly relevant for achieving the success according to the invention thatthe contact plate 6 and the base plate 3 are connected with each otherin a force transferring manner by providing direct form locking so thata movement of the base plate 3 relative to the contact plate 6 is lockedin the forward direction 17, advantageously also in the backwarddirection 18, further advantageously in all movement directions of thedevice 1.

The features described supra for the illustrated embodiment are usableindependently from each other as a matter of principle as deemedappropriate by a person skilled in the art. The individual features ofthe device 1 according to the invention, therefore, do no depend uponeach other.

REFERENCE NUMERALS AND DESIGNATIONS

1 Device

2 Undercarriage

3 Base plate

4 Super structure

5 Tow bar

6 Contact plate

7 Sideways direction

8 Connection portion

9 Topside of base plate

10 Form locking portion

11 Forward end section

12 Forward edge

13 Locking element

14 Base surface

15 Outer collar

16 Outer edge

17 Forward direction

18 Backward direction

19 Form locking section

20 Transmission section

21 Rear end section

What is claimed is:
 1. A device for compacting a substrate, the devicecomprising: an under carriage with a base arranged at the undercarriage; a superstructure which is connected to the under carriage sothat a force is transferable between the superstructure and the undercarriage and a vibrator by which the base plate of the under carriage isexcitable to vibrate; and a contact plate which is arranged at bottomside of the base plate which bottom side is oriented away from thesuperstructure so that the contact plate directly contacts the substrateto be compacted during an operation of the device, wherein the contactplate and the base plate are connected with each other so that thecontact plate and the base plate are disengageable from each otherwithout damaging the contact plate or the base plate, wherein thecontact plate includes at least one connection portion that isconfigured to engage the base plate through direct form locking so thata force transmitting connection between the contact plate and the baseplate is establishable exclusively by the connection portion, andwherein the at least one connection portion is formed at the contactplate so that the at least one connection portion extends in aninstalled position of the contact plate from a bottom side of the baseplate to a top side of the base plate that is oriented towards the superstructure and engages the super structure with the topside at thislocation.
 2. The device according to claim 1, wherein the forcetransmitting connection between the contact plate and the base plate isfree from additional connection devices.
 3. The device according toclaim 1, wherein the contact plate and the base plate are connectablewith each other and disengagable from each other without tools.
 4. Thedevice according to one of the claim 1, wherein the contact plate (6) isintegrally provided in one piece.
 5. The device according to one of theclaim 1, wherein the contact plate includes at least one outer collarthat s oriented perpendicular to a base surface of the contact plate,wherein the outer collar forms a stop surface for a corresponding outeredge of the base plate in an installed condition of the contact plate sothat a movement of the base plate relative to the contact plate in adirection towards the collar of the contact plate is blocked.
 6. Thedevice according to claim 1, wherein the contact plate is formed from asynthetic material, whose stiffness is significantly less than astiffness of the base plate, wherein a stiffness of the contact plate isat the most 0.1% of the stiffness of the base plate.
 7. The deviceaccording to claim 1, wherein the contact plate includes a plurality ofconnection portions, wherein the connection portions engage the baseplate overall so that a movement of the contact plate relative to thebase plate is blocked in a forward direction of the device as well as ina reverse direction of the device.
 8. The device according to claim 1,wherein the at least one connection portion is arranged at a forward endsection of the contact plate, and wherein the at least one connectionportion cooperates with the base plate so that the at least oneconnection portion covers a front edge of the base plate at leastpartially.
 9. The device according to claim 1, wherein at least onelocking element is arranged at the contact plate, and wherein thecontact plate is lockable at the base plate by the locking element. 10.The device according to claim 1, wherein at least a rear edge side ofthe contact plate is configured flat so that the device is configured torun with its base plate at the rear edge side onto the contact plate,wherein a thickness of the contact plate at least at the rear edge sideis not not more than 4 cm.
 11. A method for mounting a contact plate ata base plate of a device for compacting a substrate, the methodcomprising the steps: positioning the base plate and the contact platerelative to each other so that the base plate contacts the contact plateat least substantially completely; connecting the base plate and thecontact plate with each other in a force transferring manner, so that amovement of the contact plate relative to the base plate is blocked atleast in a forward direction of the device; and moving the base platerelative to the contact plate so that the base plate moves into at leastone connection portion of the contact plate so that the base plate andthe contact plate are connected with each other by direct form lockingafter inserting the base plate into the connection portion.
 12. Themethod according according to claim 11, further comprising steps: afterpositioning the base plate on the contact plate elastically expandingthe contact plate at least in a connection portion by a mounting force;and moving at least a portion of the expanded connection portion over anedge of the base plate and subsequently reducing the mounting force sothat the contact plate is applied at least with a portion of theconnection portion to a top side of the base plate due to an elasticspringback of the contact plate so that the contact plate engages thebase plate by direct form locking.